June 8 Class Session		Research Designs Internal Validity External Validity Experimental & Correlational Designs
Overhead Lecture Notes	OVERHEAD.f06.pdf Details Download 116 KB

Validity

• control of variables that may have an affect
• High Validity means can generalize from sample

Note Conventions - H
Two Types - reference JC Lectures

• Internal [causal validity] = x produces y
  • 8 extraneous variables that threaten internal validity
  • HIMPTRISM
• External [generalization beyond the sample]
  • 5 types - population, ecological, temporal, treatment variation, outcome
  • PETTO
• Statistical control
• Construct

Other types of Classification of Validity

• Content
• Criterion Related
• Construct

Types of Research Designs

Experiments involves causes, explanation of causes

Three types of Variables

• Independent [affected by amounts,
• dependent
• extraneous [confounding]

Ways to control variables

1. random assignment - gold standard for controlling variables
2. matching
3. counterbalancing
4. random sampling?
5. Holding EV constant
6. Statistical Control
7. Incorporate into research design by making it an independement variable

REREAD JC Chapter 9 - focus on Repeated Measures Design